1. Field of the Invention
The present invention relates to an air-conditioning unit and a vehicle air-conditioning apparatus, and more particularly to an air-conditioning unit and vehicle air-conditioning apparatus positioned to the front with respect to the front seat.
This application is based on Japanese Patent Applications No. 2004-8559, filed Jan. 15, 2004, No. 2004-8561, filed Jan. 15, 2004, and No. 2004-39878, filed Feb. 17, 2004, the contents of which are incorporated herein by reference.
2. Description of Related Art
As a conventional air-conditioning unit there is known a so called HVAC (heating, ventilation, and air-conditioning) module is known in which a blower is positioned at the front of and higher in a vehicle, and an evaporator is positioned at the front of and lower in the vehicle, and a heater core is positioned to the rear of and lower than the air-conditioning unit in the vehicle (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2003-34114).
However, as shown in FIG. 16, in the air-conditioning unit 100 disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, a defrost outlet 101 is provided at the top-center of the air-conditioning unit 100, and side face outlets 102 are provided on the top-rear side walls of the air-conditioning unit 100. Therefore, as shown in FIG. 17, there is a problem in that defrost ducts 101a and the face ducts 102a must be bent at sharp angles to reach the required positions, resulting in a dramatic increase in duct resistance of the ducts 101a and 102a. 
The reason for bending the face duct 102a in a U-shape as shown in FIG. 17 is the need to avoid an instrument cluster 104 positioned in front of a steering wheel 103 on the driver's side, and the need to avoid an airbag, a dashboard (not shown in drawings), and the like on the passenger's side. Reference symbol WS in FIG. 17 denotes a windshield.
Furthermore, in the air-conditioning unit 100 disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, since the heater core 105 is positioned at the lower rear of the air-conditioning unit 100, that is to say, in the vicinity of the feet (toes) of a passenger sitting in the front seat, if a crack or the like should occur in the heater core 105 or in the hot water piping (not shown in drawings) connected to the heater core 105 and hot water should leak, this leaked hot water may come into direct contact with the feet of the passenger sitting in the front seat.
Moreover, since the heater core 105 is positioned at the rear of the air-conditioning unit 100 (that is to say, on the passenger compartment side), the distance between the radiator mounted in the engine compartment (not shown in drawings) and the heater core 105 is increased, the length of the hot water piping is increased, the hot water piping must be routed to avoid the feet of the passenger sitting in the front seat, and thermal insulation material must be wound around the exposed hot water piping to guard against burns resulting from the feet of the passenger contacting the hot water piping, causing a problem in that the manufacturing process becomes complicated.
Furthermore, in the air-conditioning unit 100 disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, feet outlets 106 are provided in the side walls at the rear-center of the air-conditioning unit 100. Therefore one end of a duct (not shown in drawings) must be connected to this feet outlet 106, and the other end of the duct must be extended to the feet of the passenger sitting in the front seat, so that there are problems in that routing of the duct becomes troublesome, the duct can only extend as far as the vicinity of the ankles and shins of the passenger, and the feet of the passenger cannot be warmed sufficiently.
Moreover, in the air-conditioning unit 100 disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, when a face/feet mode (a mode wherein air is blown from the center face outlet 117, the side face outlet 102 and the feet outlet 106) is selected, the cold air passing through the evaporator 108 flows into (collides with) the warm air W passing through the heater core 105 and along the inner wall surface 107a of a wall 107 and upwards. Therefore cold and warm air are mixed in the vicinity of the area upstream of the feet outlet 106, and air at approximately the same temperature is blown from the face outlet 102 and the feet outlet 106. Therefore there is a problem in that a temperature difference to keep the head cool with cold air blown from the face outlet 102 and the feet warm with warm air blown from the feet outlet 106 is not possible
Furthermore, in the air-conditioning unit disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, component parts such as the evaporator and the heater core are housed within the main cover in a rigidly fixed manner, increasing the overall rigidity of the air-conditioning unit. Therefore there is a problem in that, at the time of a vehicle collision, the air-conditioning unit is not readily broken under an impact force, and hence there is insufficient safety in a collision.
Moreover, in the air-conditioning unit 100 disclosed in Japanese Unexamined Patent Application, First Publication No. 2003-34114, a rear feet outlet 114 is provided at the lower rear of the air-conditioning unit 100, and a flow path 115 is provided to guide the air which has been heat-exchanged in the evaporator 108 and/or the heater core 105 to the rear feet outlet 114.
Therefore a wall 116 forming the outside of the main cover, and the wall 107 formed on the front side of this wall 116 and forming the flow path 115 are formed at the rear of the air-conditioning unit 100 (that is to say, on the side opposite the rear face of the audio equipment buried in the center console).
In this manner, a double wall 116 and 107 is formed in front of the audio equipment, and the strength of this part is increased so that even if the audio equipment knocks against it in the event of a vehicle collision, it is not readily broken. If safety in the event of a collision is considered, it is necessary to provide a large distance between the air-conditioning unit 100 and the audio equipment, and immediately following a collision, maintain a distance between the audio equipment and a passenger sitting in the front passenger seat. Therefore there is a problem in that the space between the air-conditioning unit 100 and the audio equipment is wasted, sacrificing the interior space of the vehicle.